#region Header

// <file>
//     <copyright see="prj:///doc/copyright.txt"/>
//     <license see="prj:///doc/license.txt"/>
//     <owner name="Daniel Grunwald" email="daniel@danielgrunwald.de"/>
//     <version>$Revision: 2658$</version>
// </file>

#endregion Header

namespace ICSharpCode.TextEditor
{
    using System;

    /// <summary>
    /// A line/column position.
    /// Text editor lines/columns are counting from zero.
    /// </summary>
    public struct TextLocation : IComparable<TextLocation>, IEquatable<TextLocation>
    {
        #region Fields

        /// <summary>
        /// Represents no text location (-1, -1).
        /// </summary>
        public static readonly TextLocation Empty = new TextLocation(-1, -1);

        int x, y;

        #endregion Fields

        #region Constructors

        public TextLocation(int column, int line)
        {
            x = column;
            y = line;
        }

        #endregion Constructors

        #region Properties

        public int Column
        {
            get { return x; }
            set { x = value; }
        }

        public bool IsEmpty
        {
            get {
                return x <= 0 && y <= 0;
            }
        }

        public int Line
        {
            get { return y; }
            set { y = value; }
        }

        public int X
        {
            get { return x; }
            set { x = value; }
        }

        public int Y
        {
            get { return y; }
            set { y = value; }
        }

        #endregion Properties

        #region Methods

        public static bool operator !=(TextLocation a, TextLocation b)
        {
            return a.x != b.x || a.y != b.y;
        }

        public static bool operator <(TextLocation a, TextLocation b)
        {
            if (a.y < b.y)
                return true;
            else if (a.y == b.y)
                return a.x < b.x;
            else
                return false;
        }

        public static bool operator <=(TextLocation a, TextLocation b)
        {
            return !(a > b);
        }

        public static bool operator ==(TextLocation a, TextLocation b)
        {
            return a.x == b.x && a.y == b.y;
        }

        public static bool operator >(TextLocation a, TextLocation b)
        {
            if (a.y > b.y)
                return true;
            else if (a.y == b.y)
                return a.x > b.x;
            else
                return false;
        }

        public static bool operator >=(TextLocation a, TextLocation b)
        {
            return !(a < b);
        }

        public int CompareTo(TextLocation other)
        {
            if (this == other)
                return 0;
            if (this < other)
                return -1;
            else
                return 1;
        }

        public override bool Equals(object obj)
        {
            if (!(obj is TextLocation)) return false;
            return (TextLocation)obj == this;
        }

        public bool Equals(TextLocation other)
        {
            return this == other;
        }

        public override int GetHashCode()
        {
            return unchecked (87 * x.GetHashCode() ^ y.GetHashCode());
        }

        public override string ToString()
        {
            return string.Format("(Line {1}, Col {0})", this.x, this.y);
        }

        #endregion Methods
    }
}